Abrasive device



A rii 19, 1938.

A. W. WALKER ABRASIIVE DEVICE Filed Dec. 23, 1935 ljwmmmbmmw INVENTOR. AVERY w. WALKER ATTORNEY.

Patented Apr. 19, 1938 UNITED STATES PATENT OFFICE ABRASIVE DEVICE of Delaware Application December 23, 1935, Serial No. 55,721

4 Claims.

This invention relates to an abrasive device and particularly to such devices which are adapted to be used in improving or sharpening the cutting edge of tools such as knives and the like.

The primary object of the invention is to provide an abrasive device with a plurality of abrasive surfaces of different degrees of fineness, including means for supporting any of the abrasive surfaces in a horizontal operating position.

A further object of the invention is to provide a structure for the abrasive surfaces or stones which will permit any of the stones to be readily moved to a position so that a tool or knife may be sharpened thereon and to provide means for releasably securing any of the stones in such a position.

The mounting of abrasive stones in such a manner that they may be rotated and each brought into a position for tool sharpening engagement has been known and practiced in the past. It has been the conventional practice to provide a container for such an abrasive assembly which is partially filled with oil so that the abrasive stone or stones not in use during a particular tool sharpening operation are bathed and the surface thereof cleansed by the oil. One of the distasteful and unsatisfactory features of such devices is that the oil is frequently splashed or spilled from the container as a result of the movement of the abrasive stones to a tool engaging position. The oil is often splashed from the container in moving the entire assembly from one place to another within an establishment or store. These abrasive devices are often used on the counters of retail meat stores or establishments of like character and where tidiness and cleanliness are necessary adjuncts to the good will of the establishment. The splashing of oil from the container is therefore unsightly and also conducive to the collection of dust and other foreign matter which is obnoxious to the customer.

It is therefore a further object of the invention to provide a means for retaining the oil in the container when the device is moved from one point to another on the counter and when the abrasive assembly is laterally moved or vibrated during a tool sharpening operation.

In the knife sharpening devices of the past it has been customary to form the abrasive stones in the shape of an elongated rectangle and often not than one-half of an inch in thickness. A plurality of these stones are usually associated with a movable supporting structure of a complementary length to that of the stones. It has also been the conventional practice to secure the relatively long and thin abrasive stones to the movable structure by means of clamps fixed adjacent the ends of the supporting structure or rotor which tend to compress the stones along, their length. The abrasive stones have often become loose in their supports by reason of shrinkage or other internal stresses within the stones or warping of the clamping supports and it will be appreciated that any increase or decrease in the over-all length of the stones will be materially more along the length than across the width thereof. Many of the devices of the prior art also provide a single clamp to each end of the rotatable structure and thus making it necessary to provide the plurality of abrasive stones with exact similar lengths; otherwise the single clamp would not engage the various stones with equal clamping pressure, leaving one or more of the stones loose or improperly secured to the supporting structure. Accordingly, another object of the invention is to provide an improved means for securing the abrasive stones to the movable structure.

A further object of this invention is to improve the abrasive device in various details of construction so as to render a compact, easily adjusted, diuable, and at the same time a unit structure which is relatively light in weight and which may be readily moved from place to place.

In the accompanying drawing,

Fig. l is a plan view of the abrasive device with a portion of the cover removed;

Fig. 2 is a longitudinal, vertical, and in part a sectional View taken on the lines II-II of Fig. 1; Fig. 3 is a transverse sectional viewtaken on the lines III-III of Fig. 2; and

Fig. 4 is a perspective view of a portion of the I abrasive supporting member or rotor..

Referring to the drawing, a base II is provided for supporting the abrasive assembly. The base is constructed with a relatively wide, flat under surface l2 so that the device may rest solidly upon the counter of a meat store or any other flat surface where it may be placed in operation. The base H in reality is the bottom portion of an elongated reservoir orreceptacle l3. A portion of the base extends outwardly and upwardly along the edge I l and a channel i5 is thus provided around the entire receptacle and the upper surface of the base ii. In the operation of the device, the receptacle or reservoir i3 is partially filled with oil to bathe or cleanse the abrasive stones and while the present invention includes means for reducing the escape of oil from the reservoir, the channel I5 is nevertheless provided and it is desirable to catch any small amount of oil which may be inadvertently spilled or splashed from the reservoir as a result of abnormal operation of the device. The supporting base II including the receptacle may be a metal casting or metal stamping of suitable form. However, in a preferred embodiment of the invention, the base II and the walls of the receptacle |3 and a cover |6 for the receptacle are all formed from a moulding compound having a binder of phenol-formaldehyde resin or the like which has been found to provide a durable casing which materially reduces the weight of the device.

Near the ends of the base a pair of partitions l1 and 8 project vertically and thus form the end walls of the receptacle |3. These partitions are formed relatively thick so that an adequate support is provided for the abrasive assembly as will be hereinafter described.

Along the sides of the base H a pair of partitions 9 and 26 extend vertically to provide the side walls for the receptacle l3. The end partitions l1 and I8, and the side partitions l9 and 20 are joined at the four corners of the base to form a liquid tight receptacle. In actual construction, the base and reservoir are molded as one complete unit. A cover l6 adapted to rest upon the top edges of the receptacle walls is provided to cover the entire reservoir.

A relatively coarse abrasive stone 2| and an abrasive stone of a finer grain 22, are mounted on a supporting member or rotor shown generally at 23 within the receptacle l3. The supporting member or rotor is made of metal and shaped to a length slightly less than the distance between the end partitions I? and IS. The rotor is provided with a flat surface 24 extending along what is shown as the top of the rotor 23 and throughout the length thereof. A similar flat surface 26 is provided along the bottom of the rotor. A flange 21 formed from an integral part. of the metal rotor 23 is provided along the entire length of the supporting member. It is to be noted that the flange 21, along its inner side, projects vertically from the flat surface 24. An oppositely disposed flange 28 is provided along the bottom of the rotor and this flange also extends along the entire length of the supporting member. The supporting member or rotor 23 may be die-cast of some light Weight metal or alloy, and to further reduce the Weight of the entire device the center portion between the ends of the rotor may be hollow with a plurality of cross members 3| provided to rigidly support the flat surface portions 24 and 26.

A rib 32 is provided at the inner end of the rotor and extends from one side thereof to the other. A similar rib 33 is provided at the opposite end of the rotor. These ribs may be cast integrally with the rotor and are provided for the purpose of strengthening the abrasive supporting structure at the mounting point. The outer end 34 of the rotor is recessed as indicated at 36 to receive a plate 31. The opposite end 38 of the rotor, is similarly recessed as indicated at 39, to provide a space for the plate 4|. A bushing 42 is fastened to the plate 31 and extends therefrom in a perpendicular manner to form a shaft for the rotor. A similar bushing 43 is provided affixed to the plate 4| and a. shaft is thus provided for each end of the rotor. The shaft or bushing 42 is adapted to extend through a bearing 44 in the end wall ll of the receptacle. At the opposite end of the receptacle a similar bearing 46 is provided in the end wall IE to receive the bushing or shaft 43 which extends from the rotor at that end. The plate 31 carrying the bushing or hollow shaft 42 is secured to the rotor by means of a bolt 41, the head of which is adapted to engage the rib 32 with the shank portion thereof extending through an opening 48 provided in the end of the rotor. The bolt 41 also extends through the bushing or hollow shaft 42 and the threaded portion thereof is adapted to engage an internally threaded hand wheel 49. The shoulder 5| of the hand wheel, by its engagement with the end 52 of the bushing 42, thereby holds the plate 37 in the recess 36 and a rigid shaft is thus provided extending from the end 34 of the rotor when the shoulder 5| of the hand wheel 49 is brought into engagement with the end 52 of the hollow shaft or bushing. The end Wall |8 at the opposite end of the receptacle is provided with a bearing 46 and is adapted to receive the bushing or hollow shaft 43. The plate 4|, carrying the bushing 43, is secured in the recess 39 by means of a bolt 51, a hand wheel 59 in a manner similar to that described in connection with the opposite end of the rotor.

In the actual assembly of the device the bushings or hollow shafts 42 and 43 are first inserted respectively in the bearings 44 and 46. The rotor is then held along the open top of the receptacle in such a manner that the plate 31 will engage the recess 36 and the plate 4| the recess 39. The rotor is then moved into the receptacle and the bolts 4'! and 51 are inserted in the openings 48 and 58, through the bushings or hollow shafts 42 and 43 and into threaded engagement with the hand wheels 49 and 59.

The abrasive supporting member or rotor 23 is thus rotatably supported within the receptacle and it is to be noted that the length of the rotor is slightly less than that of the receptacle and that the bearings and shafts will permit axial translation of the abrasive supporting member or rotor 23.

After the rotor is mounted within the receptacle as above described, the supporting member 23 may be turned 180 in either direction and the flat surfaces 24 and 26 will therefore extend in a plane perpendicular to the supporting base" The abrasive stones 2| and 22 are then positioned along the flat surfaces 24 and 26. One edge of the abrasive stone 2| is brought into engagement with the flange 21 along the entire length of the abrasive. One edge of the abrasive stone 22 is positioned adjacent the flange 28 which also extends along the length of the rotor. The abrasive elements 2| and 22 are secured, in above described position, to the rotor by means of a clamp member 6|. The clamp 6| is formed to a length which is the same as the rotor and the abrasive stones and is provided with a relatively wide, flat surface 62 adapted to engage the abrasive stones along their edges 63 and 64. The clamp member is held in engagement with the edges of the abrasive stones by a plurality of screws 66 which are adapted to engage the cross ribs 32 and 33 and the cross member 3|. The abrasive stones are thus held securely to the rotor by means of the flange portions 21 and 28 of the rotor and the clamp member 6| all of which extend along the entire length of the abrasive stones.

The abrasive stone 2| formed of relatively coarse grain, may therefore be rotated and brought to a horizontal position above the walls of the receptacle or in a position for tool sharpening engagement as shown in the drawing. The abrasive stone 22 is then positioned with its flat surface 180 removed from the flat surface of the stone 2|. The receptacle l3 is partially filled with oil to a point where the stone in the under position as above described, will be covered by and bathed in the oil.

It is desirable that the abrasive stones be held in a tool engagement position against rotation and it is for this purpose that a locking mechanism is provided. The end wall I! of the receptacle is provided with a pair of tapered pins H and 12 projecting inwardly from the wall l1 and toward the end 34 of the rotor. The pins II and I2 are positioned in such a manner that they will engage a pair of holes 13 and 14 formed in the end plate 31 and thus prevent rotation of the abrasive supporting member or rotor. A

spring 61 is provided to encircle the hollow shaft or bushing 42 and is mounted thereon in such a manner that one end of the spring will engage the shoulder 5| of the hand wheel 49 and the opposite end of the spring will engage the outer surface of the end wall IT. The spring 61 tends to move the abrasive supporting member 23 axially so that the end 34 thereof is moved toward the end wall l1. When the abrasive stone 2! is in a horizontal position at the top of the receptacle, the pin II will engage the opening 14 and the pin 12 will engage the hole 13 and thus prevent rotation of the abrasive supporting member 23. The abrasive supporting member however, may be rotated to bring the abrasive stone 22 to a tool engagement position at the top of the receptacle by compressing the spring 8'! which will cause the end 34 of the rotor to move away from the pins H and 12. After the ends of the pins have cleared the openings 13 and 14, the pressure on the spring 61 may be released and further turning of the hand wheels 49 and 59 will cause the abrasive supporting member 23 to be rotated and when the opening 13 is in alignment with the pin II and the hole 14 is opposite the end of the pin 12, the spring 61 will cause axial translation of the rotor structure and bring the pin 'Il into engagement with the opening 13 and the pin 12 into engagement with the opening 14 and thus releasably lock the abrasive supporting member against rotation.

The oil used in the receptacle must necessarily be a high quality mineral oil since the tools or knives sharpened on devices of this character are often used to cut meat and food. It is therefore desirable to prevent the waste of such oil and it is also desirable to prevent contamination thereof. In cutting meat, small particles of fat often cling to the blade of the knife, and during the sharpening operation it is desirable to prevent the movement of these particles into the oil and cause contamination thereof. A fin I6 is therefore provided along one side of the abrasive supporting member 23, which extends throughout the length thereof. The fin 16 radiates from the side of the rotor to a point near the side wall l9 when the abrasive stone 2| is in an uppermost horizontal position, and thus substantially closes the area along the side of the rotor above the oil. A somewhat similar fin 11 is provided along the opposite side of the rotor and along the entire length thereof. The fin I1 however, is formed as a part of the clamp member 6|, but when the clamp is in place as indicated in Fig. 3, the fin 11 substantially closes the area above the oil between the side wall 20 and the clamp side of the rotor. The fins 16 and 11 are carried by the abrasive supporting structure 23 and irrespective of which of the stones, 2| or 22, is at the top horizontal position, the area above the oil is always substantially closed by the fins. It is apparent therefore that considerable oil is conserved in the bottom of the receptacle since the fins substantially close the area between the rotor and the side walls and thus prevent splashing of the oil from the reservoir and at the same time reduce the amount of foreign particles that would otherwise enter the oil reservoir.

1 claim:

1. An abrasive device comprising an elongated receptacle, elongated abrasive supporting means mounted within said receptacle, a plurality of elongated abrasive elements associated with said supporting means, clamping means carried by said supporting means and extending along the length thereof, said clamping means adapted to clamp said abrasive elements along the entire length thereof and secure the same to said supporting means.

2.'An abrasive device comprising an elongated receptacle having a rectangular opening at the top thereof and containing a supply of liquid, a

pair of substantially flat, rectangular shaped abrasive elements, an elongated abrasive supporting member rotatably mounted within said receptacle with the major portion thereof above the surface of the liquid, said abrasive elements being clamped to said supporting member along the entire length of their longest sides and with the fiat surfaces thereof arranged in substantial- 1y a one hundred and eighty degree circumferentially spaced relation and the surface of one of said abrasive elements normally being below the surface of the liquid, a pair oflongitudinally extending fins associated with said supporting member in a one hundred and eighty degree circumferentially spaced relation whereby the fiat surface of the upper rectangular shaped abrasive element and the two fins substantially close the opening in said receptacle.

3. In an abrasive device comprising a receptacle constructed and arranged to hold a supply of liquid, and having a bearing in each of the end walls, an abrasive supporting rotor, a shaft secured to each end of said rotor, each of said shafts extending respectively into rotatably supporting engagement with each of said bearings, said rotor assembly having a pair of apertures in one end thereof, a pair of tapered pins rigidly secured to and projecting inwardly from one end wall of said receptacle, a spring associated with one of said shafts urging axial translation of said rotor and the apertured end thereof into wedglng engagement with said pins whereby gyration of said rotor is prevented.

4. An abrasive device comprising a receptacle havinga bearing in each of two opposite walls, an abrasive assembly of shorter length than the distance between said opposite walls rotatably supported by said bearings and having a plurality of apertures in one end thereof, a hand wheel secured to each end of said assembly, a plurality of pins projecting from one of said walls towards the apertured end of said assembly and resilient means for urging axial translation of said assembly and the apertured end thereof into engagement with said pins to releasably lock said supporting member against rotation whereby the same may be unlocked and rotated by movement of said hand wheels.

AVERY W. WALKER. 

